A typical lock comprises a lock bolt that is received within a keep when the lock is activated. When the lock is deactivated the lock bolt can be withdrawn from the keep. A lock mechanism is typically used to selectively restrict or control movement of a lock and/or control the lock bolt.
Certain locks and lock mechanisms, such as those for key boxes or safes and the like, are required to be particularly robust. These types of locks must be able to withstand large forces, particularly when attacked, yet still operate smoothly and reliably.